Los Angeles County sheriff's deputies responded to a report of an assault with a deadly weapon in the 100 block of S. 6th Avenue around 1 a.m., sheriff's Lt. Daniel Vizcarra said.
Three men had been involved in an altercation where one of them produced a knife and stabbed the two victims, Vizcarra said.
A man was taken to a hospital, where he was pronounced dead. Another man was also treated at a hospital, but authorities haven't released details on his condition.
Authorities detained one person, Vizcarra said.
Further details were not immediately released.
Anyone with information about the stabbing is asked to contact the L.A. County Sheriff's Department's Homicide Bureau at (323) 890-5500.